Work will be continued on the development of methods for the production and purification of human type II (immune) interferon. Production will be scaled up by the use of buffy coats from the blood bank instead of fresh blood. A number of purification steps will be evaluated including chromatography on controlled pore glass, bule sepharose, Con-A sepharose, and gel filtration of Biogel P-150. Purified Le, F and T interferons will be compared in their biological activities including antiviral action, growth inhibitory action, activation of natural killer (NK) cell activity, and induction of 2'5' (pA)n synthetase activity.